The spread of bad advice.
I figure some of you may want to know about this ( and some of you won't ) Or don't want to believe it.
This is not new by any stretch, I have seen this for years on heads and cylinders.
I have been doing alot of Polaris 700/800 crankcase machining and line boring and this problem started effecting the repair of some cases.
Ok, these little 3M type cleaning wheels( there all different types ) but they all do about the same thing. You put them on a mandrel and insert them into a HIGH SPEED air tool ( 20,000 RPM ) I know what some of you are thinking............( I got the touch !! ) I control the speed, and I lightly skim it accross the surface not doing any damage.
WRONG,WRONG.WRONG.
These little high speed items are pushed heavily by tool truck drivers accorss the country to save time.
I will tell you this........... More car and truck blocks and heads have been ruined by these tools then any other tool ever produced.
I personaly had a 1985 Honda Civic I bought with 90,000 miles on it, Head gasket failed at 105,000 miles, took it in and had it replaced the second head gasket failed in 30,000 miles took it in and had it replaced again, the thrid gasket failed in less then 5000 miles. I took the the car back to the shop and I said this is impossible I told him to take it apart and I want to see the gasket. he called me and told me it was apart and to come over.
I walk into the shop and there on top the wheel well was the old gasket that was blowen out right between cylinder 2 & 3 and 3 & 4 in the narrow area in the centers where the cylinders get close together on the block.
And guess what lay there hooked to the air hose..............I said you don't use that to clean the block and the head do you................ He said I sure do what the hell else would I use........ You think I got time to hand scrape these blocks???
I said you single handedly wrecked my motor with that ( POS ) We argued alitte, and I said I will prove it.
I want the motor pulled and I will come get it and the head, I will machine both of them and bring them back and will try this again.
Of coruse he tried to tell me that this happens from time, and also driving it with a blowen head gasket ( WRONG ) the block is cast iron and the head is alum. I didn't drive it with it blowen --------- And if I did it would ruined the head not the block. Head gaskets blow on these motors because of dissimlar metal heads and blocks. Alum head on a cast iron block both expand at a different rate and gaskets can fail.
Ok, Head & block both machined ( on a machine with CBN tooling ) not some piece of sh!t rotary broach that makes things worse then they were before you started because the machine shop is so far behind the times it should be closed. Rotary broaches should be outlawed.
Ladies & Gentalmen - When you take your stuff to a dealer make sure you find out where they take your stuff to get machined.....
Most gaskets have a required finish they need to have ( the smoother the surface the better the gasket will bite onto the surface.
DON'T EVER let someone tell you that gaskets bite better when the surface has machining grooves..........If you can feel them with your finger nail in ANY WAY there to rough. ( Seeing machine marks yes, Feel them..........No )
OPPPPSSS!!!!!!! By the way, My old Honda went over 125,000 miles on the last head gasket and I sold it and it still runs today.
I have had 3 crankcase come thru the shop that were complete destroyed by these cleaning tools............. And yes a few came thru that also did pass but it was close.
Just think............. If the ones that were close had been done one more time the crankcases would be to tight and they would stick a bearing and lock rite-up.
These are Exotic little motors that make unbelievable amountof power for what they are, These are not 1968 Chevy small blocks and the ONLY way to clean them is by hand or expensive cleaning machines.
Do yourself, And or your customers a HUGE favor..........DO NOT CLEAN WITH A HIGH SPEED AIR GRINDER.
There is no way for you to imagin how much metal these tools remove.
Dan.
I figure some of you may want to know about this ( and some of you won't ) Or don't want to believe it.
This is not new by any stretch, I have seen this for years on heads and cylinders.
I have been doing alot of Polaris 700/800 crankcase machining and line boring and this problem started effecting the repair of some cases.
Ok, these little 3M type cleaning wheels( there all different types ) but they all do about the same thing. You put them on a mandrel and insert them into a HIGH SPEED air tool ( 20,000 RPM ) I know what some of you are thinking............( I got the touch !! ) I control the speed, and I lightly skim it accross the surface not doing any damage.
WRONG,WRONG.WRONG.
These little high speed items are pushed heavily by tool truck drivers accorss the country to save time.
I will tell you this........... More car and truck blocks and heads have been ruined by these tools then any other tool ever produced.
I personaly had a 1985 Honda Civic I bought with 90,000 miles on it, Head gasket failed at 105,000 miles, took it in and had it replaced the second head gasket failed in 30,000 miles took it in and had it replaced again, the thrid gasket failed in less then 5000 miles. I took the the car back to the shop and I said this is impossible I told him to take it apart and I want to see the gasket. he called me and told me it was apart and to come over.
I walk into the shop and there on top the wheel well was the old gasket that was blowen out right between cylinder 2 & 3 and 3 & 4 in the narrow area in the centers where the cylinders get close together on the block.
And guess what lay there hooked to the air hose..............I said you don't use that to clean the block and the head do you................ He said I sure do what the hell else would I use........ You think I got time to hand scrape these blocks???
I said you single handedly wrecked my motor with that ( POS ) We argued alitte, and I said I will prove it.
I want the motor pulled and I will come get it and the head, I will machine both of them and bring them back and will try this again.
Of coruse he tried to tell me that this happens from time, and also driving it with a blowen head gasket ( WRONG ) the block is cast iron and the head is alum. I didn't drive it with it blowen --------- And if I did it would ruined the head not the block. Head gaskets blow on these motors because of dissimlar metal heads and blocks. Alum head on a cast iron block both expand at a different rate and gaskets can fail.
Ok, Head & block both machined ( on a machine with CBN tooling ) not some piece of sh!t rotary broach that makes things worse then they were before you started because the machine shop is so far behind the times it should be closed. Rotary broaches should be outlawed.
Ladies & Gentalmen - When you take your stuff to a dealer make sure you find out where they take your stuff to get machined.....
Most gaskets have a required finish they need to have ( the smoother the surface the better the gasket will bite onto the surface.
DON'T EVER let someone tell you that gaskets bite better when the surface has machining grooves..........If you can feel them with your finger nail in ANY WAY there to rough. ( Seeing machine marks yes, Feel them..........No )
OPPPPSSS!!!!!!! By the way, My old Honda went over 125,000 miles on the last head gasket and I sold it and it still runs today.
I have had 3 crankcase come thru the shop that were complete destroyed by these cleaning tools............. And yes a few came thru that also did pass but it was close.
Just think............. If the ones that were close had been done one more time the crankcases would be to tight and they would stick a bearing and lock rite-up.
These are Exotic little motors that make unbelievable amountof power for what they are, These are not 1968 Chevy small blocks and the ONLY way to clean them is by hand or expensive cleaning machines.
Do yourself, And or your customers a HUGE favor..........DO NOT CLEAN WITH A HIGH SPEED AIR GRINDER.
There is no way for you to imagin how much metal these tools remove.
Dan.
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